Explosive actuated punch

ABSTRACT

A explosive actuated punching tool comprising (a) a handle, (b) a frame, (c) a breech block, (d) a firing mechanism, (e) a cartridge chamber, (f) adjustable means for holding a workpiece, (g) a movable piston driven by the gases created by firing a cartridge, (h) a punch moved by the piston, (i) means for controlling the length of the stroke of punch, (j) a die, and (k) a punch slug deflector.

United States Patent 1191 I 3,863,341 Ramer I Feb. 4, 1975 [54] EXPLOSIVE ACTUATED PUNCH 3,159,025 12/1964 Pais 30/DIG. 4

[76] Inventor: James L. Ramer, Rt. 1, Box 155, FOREIGN PATENTS OR APPLICATIONS Sulllvan, 63030 271,834 1/1965 Australia 30/DIG. 4

[22] Filed: Aug. 27, 1973 D Primary Examiner-Al Lawrence Sm1th [2]] Appl' 392,162 Assistant ExaminerJ. T. Zatarga t Attorney, Agent, or Firm-James E. Noble; William G. 52] vs. C]. 30/358, 30/DIG. 4 Gapcynski; Lawrence Neureither [51] Int. Cl B26f l/02, 826d 7/26 [58] Field of Search 30/358, DIG. 4 [57] ABSTRACT A explosive actuated punching tool comprising (a) a [56] References C'ted handle, (b) a frame, (c) a breech block, (d) a firing U E STATES PATENTS mechanism, (e) a cartridge chamber, (f) adjustable 1,915,435 6/1933 Miller 30/358 x me for holding a workpiece, (g) a movable piston 2,132,148 10/1938 30/D1G. '4' driven by the gases created by firing a cartridge, (h) a 2,775,762 1/1957 l-iilti 30/358 X pun h moved by the piston, (1) means for controlling 2,974,651 3/1961 Mame" 30lDIG- 4 the length of the stroke of punch, (j) a die, and (k) a 3,024,531 3/1962 Haskell et al.. 30/DIG. 4 punch slug deflector. 3,074,165 l/1963 Davis 30/D1G. 4 3,108,558 10/1963 Galvin 30/358 X 4 Claims, 8 Drawing Figures PATENTED 4|975 3,853,341

' SHEET 10F 2 F|G.I v 38 PATENTEUFEB 3,863,341

SHEEI' 2 BF 2 EXPLOSIVE ACTUATED PUNCH The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon. I

BACKGROUND OF THE INVENTION .1. Field of the Invention This invention relates to powder activated punching tools.

2. Description of the Prior Art Explosive activated punching tools are known. Many prior explosive operated punching tools are floor mounted shop punches. Some portable powder operated punches are also known. The explosive activated punches which are known normally have a punching stroke of a fixed length. These punches consist of an exploding chamber located adjacent to a punching means. An explosive powder or similar explosive is ignited in the chamber. The explosion causes an expansion of the gases in the exploding chamber thereby forcing the punching means through a punching stroke. Such a punch often overruns the workpiece.

SUMMARY OF THE INVENTION the punch ram to the piston, the length of travel of the piston can be predetermined. A full description of these components, their further components and operation may be understood by reference to the Figures and explanation below.

One object of the invention is to provide a hand-held portable tool which will provide smooth holes equivalent to a full-sized floor-mounted punch.

Another object of the invention is vto provide a punching tool in which the length of the punching stroke is controlled and'is dependent upon the sizeof the workpiece.

Another object of the invention is to provide a punching tool which is safe to operate. Another object of the invention is to'provide a punching tool in which the punch and die may be changed to vary the size and shape of the hole to be punched.

Other objects of the invention will be apparent from the description below.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a vertical section view of an embodiment of the punch, containing a cartridge before the punch is operated.

FIG. 2 is a view similar-to FIG. 1 showing the ram extended, with the punch ram and piston in their extreme downward position after firing.

FIG. 3 is a fragmented sectional view of the piston ram, punch and variable stroke exhaust valve showing the punch ram extended and the position of the variable stroke exhaust valve before firing.

FIG. 4 is a top view showing the handle in the locked position and indicating the movement and view of the handle in the unlocked position.

FIG. 5 is a fragmented sectional view .of the handle, breech and extractor indicating their operation. FIG. 6

is fragmented view of the handle and breech block showing the operation of the cocking mechanism and the safety.

FIG. 7 is a view along line 7-7 of FIG. 1 showing the groove created by the interrupted thread in which the variable exhaust valve moves.

FIG. 8 is a top view along line 8-8 of FIG. 1 showing the stud.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, the handle I is made up of the trigger 12, the trigger pin 36, the trigger spring 13, the trigger spring bearing nose 39, the safety 11, the safety pivot pin 38, the cocking handle 14, the firing pin striker 17, the firing pin striker driving spring 35, the firing pin striker retaining nut 34, which retains the firing pin striker 17 in its cavity against the firing pin striker driving spring 35 while the punch is beingoperated, the sear 30, the sear spring 15, the searretaining and adjustingscrew 16 which retains the sear 30 and its cavity against the compressed sear spring 15 and allows adjustment of its position, and the locking bolt 48, which is an integral part of the handle 1.

The breech block 2 consists of the following items: the breech block pivot pin 3, the firing pin 18, the firing pin retaining nut 40 which retains the firing pin 18 in the breach block 2 while the punch is being operated, the firing pin withdrawal spring 41, and the locking bolt retention pin 33 across the locking bolt entry cavity 19. The main frame 4 consists of the following items: the extractor 32 and extractor pivot pin 20, the piston return spring cavity cap 28, the piston return spring cavi ty 29, the three die retention and aligning screws 31, the anti-rotation lock 43, the anti-rotation lock pivot pin 42, the anti-rotation lock withdrawal spring 44, the exhaust port 26, and the punching port- 10. v

The piston 5 consists of the following itemsz'a hardened anti-erosion, flame resisting insert 24, the variable stroke exhaust valve 25, and integral stud 27 to engage the piston return spring 47 and an interrupted thread 46 to allow the variable stroke exhaust valve to travel when the punch ram 6 is screwed in or out.

The punch ram 6 consists of the following items: the punch retaining nut 7, an anti-rotation lock cavity 45 for the engagement of the anti-rotation lock 43.

The punching deflector consists of the punch slug deflector 50 and the punch slug deflector attaching screw OPERATION OF THE PUNCH Operation of the punch is accomplished by rotating handle I, counter-clockwise about the locking bolt 48 (integral with the handle),the reby disengaging the locking stud 23 from its locking cavity 19. After the handle unlocks, pull. the handle away from the punch. As the handle is raised the locking stud 23 will engage locking bolt retention pin 33, forcing the breech block 2 to rotate about the pivot pin 3, and lifting the breech block 2 clear of the explosive cartridge chamber 22. The breechblock 2 will engage the extractor lever 32 forcing the extractor lever 32 to pivot about the extrac-' stroke exhaust valve 25 moves within the groove 62 of the interrupted thread, always resting on the shoulder 61 of the punch ram 6. With the safety lever 11 engaging the trigger bar 12, the cocking handle 14 is drawn upward away from handle 1 and breech 2 until the sear 30 engages the firing pin striker 17, retaining the firing pin striker in the cocked position. The safety lever 11 is then disengaged from the trigger l2, and the trigger 12 is depressed, the' trigger l2 pivoting clockwise about the trigger pivot pin 36. Since the sear 30 is retained in its cavity by the sear adjusting and retaining screw 16 and the cavity is part of the trigger 12, the sear 30 is pulled away from the firing pin striker 17 as the trigger 12 rotates, allowing the disengagement of the sear 30 from the firing pin striker 17. The firingpjn striker 17,, along with the cocking'handle 14, is driven downward by the firing pin striker driving spring 35. The firing pin striker 17 strikes the firing pin 18, driving the firing pin 18 into the primer in the base of the explosive cartridge in the explosive cartridge chamber 22, detonating the explosive mixture within the explosive cartridge. The gases, at very high pressures, drive the piston 5 and the variable stroke exhaust valve 25, the punch ram 6,

punch 8 and punch retaining nut 7 downward with sufficient force to drive the punch 8 through the member to be punched. The resulting punching slug is ejected through the base of die 9 through the punching port 10 and is stopped in its travel by the punch slug deflector 50. The excess gases used in driving the piston 5 are exhausted through the exhaust port 26. The length of the stroke of the piston 5 is controlledby the distance the variable stroke-exhaust valve 25 must travel to uncover the exhaust port 26, therefore overrunning of the punch 8 is prevented. The piston 5, and all connected parts, are returned to an upstroke by the piston return spring 47. 1

To removethe punch 8, the anti-rotation lock 43 is depressed, thereby engaging the anti-rotation lock cavity 45 in the side of the punch ram 6. As long as the anti-rotation lock 43 engages the anti-rotation lock cavity 45 the punch ram 6 is held in place and prevented from rotating. A wrench of appropriate size is applied to the punch retaining nut 7 and the punch retaining nut 7 is removed allowing the punch 8 to be removed. To replace the punch 8, a procedure reverse to the one stated above is instituted. To remove the die 9 from the punch body 4 the three aligning screws 31 are un-' screwed partially and the die 9 is lifted from the die seat in the punch body 4'. To replace the die 9, a reverse procedure to the above-stated process is used.

All springs are compression springs and are in the following locations: the piston return spring 47, the antirotation lock spring 44, the firing pin retention or withdrawal spring 41, the firing pin striker driving spring 35, the sear spring and the trigger spring 13.

1 claim:

1. In an explosive activated punching tool the improvement comprising a main body, a longitudinal reto a fully retracted position whereby when said ram and cess located in said main body, a cartridge chamber communicating with said recess, means for detonating a cartridge placed in said cartridge chamber, a piston slidably received in said recess, a ram slidably received in said recess below said piston and adjustably axially joined to said piston, said ram having a shoulder within said recess an axial recess in said piston, a longitudinal member slidably received in said axial recess and resting on said shoulder such that said member moves with said ram upon axial adjustment of said ram relative to said piston, and a single exhaust port in said main body for exhausting gases from said longitudinal recess, said exhaust port being disposed in the path of travel of said longitudinal member and cooperating with said longitudinal member and with said longitudinal recess whereby adjustment of the ram relative to the piston will vary the distance of travel of the longitudinal member before uncovering the exhaust port so that in any position of relative adjustment for varying thicknesses of material to be punched when a cartridge in said cartridge chamber is detonated by said means for detonating'a cartridge the explosion which results from the detonation forces the gases in said cartridge chamber and longitudinal recess to expand and force said piston, said ram and said longitudinal member to move in said longitudinal recess until said longitudinal member uncovers the exhaust port and allows the gases to escape through said exhaust port therebyenabling the length of stroke of the punching tool to be varied according to the thickness of material to be punched.

2. The structure defined in claim 1 wherein said longitudinal member is a rod of a length such that its end opposite the shoulder is flush with the end of the piston opposite the ram when the piston and ram are adjusted said piston are adjustably extended the end of said rod opposite said shoulder moves away from the end of said piston opposite said ram and towards said exhaust port in the direction of extension a distance equal to the length of extension thereby decreasing the length of the stroke of the explosive activated punching tool an amount equal to the length of extension.

3. An explosive activated punching tool as defined in claim 3 further comprising a breech block mounted for rotation about an axis normal to the longitudinal axis of said main body, a handle including trigger means, firing pin means and cocking means cooperating with said breech block, said handle rotatable about a locking bolt disposed normal to the axis of rotation of said breech block and engaging a third recess in main body for selectively locking and unlocking said handle relative to said main body, said breech block being rotated as said handle is raised and lowered, said cartridge chamber communicating with said breech block, sear means connected to said trigger means for activating said firing pin means, cartridge retractor means coop-- erating with said breech block for removing spent cartridges from said cartridge-chamber upon rotation of said breech block, means carried by said main body and engaging said ram to prevent axial rotation thereof, punch means removably connected to said ram, die holder means carried by said main body in aligned, spaced relation with said punch means and means for deflecting material removed by operation of said punch.

4. The structure defined in claim 1 wherein a punch is attached to said ram, a die is disposed'in said main body in alignment with said punch and a chamber is located below said die whereby when said explosive actuated punching tool is operated said chamber retains the resulting punchings. 

1. In an explosive activated punching tool the improvement comprising a main body, a longitudinal recess located in said main body, a cartridge chamber communicating with said recess, means for detonating a cartridge placed in said cartridge chamber, a piston slidably received in said recess, a ram slidably received in said recess below said piston and adjustably axially joined to said piston, said ram having a shoulder within said recess an axial recess in said piston, a longitudinal member slidably received in said axial recess and resting on said shoulder such that said member moves with said ram upon axial adjustment of said ram relative to said piston, and a single exhaust port in said main body for exhausting gases from said longitudinal recess, said exhaust port being disposed in the path of travel of said longitudinal member and cooperating with said longitudinal member and with said longitudinal recess whereby adjustment of the ram relative to the piston will vary the distance of travel of the longitudinal member before uncovering the exhause port so that in any position of relative adjustment for Varying thicknesses of material to be punched when a cartridge in said cartridge chamber is detonated by said means for detonating a cartridge the explosion which results from the detonation forces the gases in said cartridge chamber and longitudinal recess to expand and force said piston, said ram and said longitudinal member to move in said longitudinal recess until said longitudinal member uncovers the exhaust port and allows the gases to escape through said exhaust port thereby enabling the length of stroke of the punching tool to be varied according to the thickness of material to be punched.
 2. The structure defined in claim 1 wherein said longitudinal member is a rod of a length such that its end opposite the shoulder is flush with the end of the piston opposite the ram when the piston and ram are adjusted to a fully retracted position whereby when said ram and said piston are adjustably extended the end of said rod opposite said shoulder moves away from the end of said piston opposite said ram and towards said exhaust port in the direction of extension a distance equal to the length of extension thereby decreasing the length of the stroke of the explosive activated punching tool an amount equal to the length of extension.
 3. An explosive activated punching tool as defined in claim 3 further comprising a breech block mounted for rotation about an axis normal to the longitudinal axis of said main body, a handle including trigger means, firing pin means and cocking means cooperating with said breech block, said handle rotatable about a locking bolt disposed normal to the axis of rotation of said breech block and engaging a third recess in main body for selectively locking and unlocking said handle relative to said main body, said breech block being rotated as said handle is raised and lowered, said cartridge chamber communicating with said breech block, sear means connected to said trigger means for activating said firing pin means, cartridge retractor means cooperating with said breech block for removing spent cartridges from said cartridge chamber upon rotation of said breech block, means carried by said main body and engaging said ram to prevent axial rotation thereof, punch means removably connected to said ram, die holder means carried by said main body in aligned, spaced relation with said punch means and means for deflecting material removed by operation of said punch.
 4. The structure defined in claim 1 wherein a punch is attached to said ram, a die is disposed in said main body in alignement with said punch and a chamber is located below said die whereby when said explosive actuated punching tool is operated said chamber retains the resulting punchings. 